1. Technical Field
This invention relates generally to an ignition system for an internal combustion engine, and more particularly to an ignition coil for an ignition system.
2. Related Art
Ignition coils commonly have an outer shell that houses a central magnetic core with secondary or high voltage windings and primary or low voltage windings disposed between the magnetic core and the shell. Typically, the secondary high voltage windings are wound over a continuous cylindrical path on an outer surface of a secondary spool, with the magnetic core being received in the secondary spool, and the primary low voltage windings are wound on an outer surface of a primary spool, wherein the secondary spool is received concentrically within the primary spool. Unfortunately, parasitic capacitance in these electrical windings unavoidable and undesirable. The parasitic capacitance exists between the individual windings simply because of their proximity to each other. The individual windings, particularly with regard to the high voltage secondary windings given their increased number in relation to the primary low voltage windings, often acts as parallel capacitors, due to their closely spaced, abutting relation to one another. As a result, any change in the voltage across the coil requires extra current to charge these intrinsic capacitors. Accordingly, the efficiency, and thus, the performance of the ignition coil for a given current is reduced.